All Chapters
Chapter 214
Chapter 213
Chapter 212
Chapter 211
Chapter 210
Chapter 209
Chapter 208
Chapter 207
Chapter 206
Chapter 205
Chapter 204
Chapter 203
Chapter 202
Chapter 201
Chapter 200
Chapter 199
Chapter 198
Chapter 197
Chapter 196
Chapter 195
Chapter 194
Chapter 193
Chapter 192
Chapter 191
Chapter 190
Chapter 189
Chapter 188
Chapter 187
Chapter 186
Chapter 185
Chapter 184
Chapter 183
Chapter 182
Chapter 181
Chapter 180
Chapter 179
Chapter 178
Chapter 177
Chapter 176
Chapter 175
Chapter 174
Chapter 173
Chapter 172
Chapter 171
Chapter 170
Chapter 169
Chapter 168
Chapter 167
Chapter 166
Chapter 165
Chapter 164
Chapter 163
Chapter 162
Chapter 161
Chapter 160
Chapter 159
Chapter 158
Chapter 157
Chapter 156
Chapter 155
Chapter 154
Chapter 153
Chapter 152
Chapter 151
Chapter 150
Chapter 149
Chapter 148
Chapter 147
Chapter 146
Chapter 145
Chapter 144
Chapter 143
Chapter 142
Chapter 141
Chapter 140
Chapter 139
Chapter 138
Chapter 137
Chapter 136
Chapter 135
Chapter 134
Chapter 133
Chapter 132
Chapter 131
Chapter 130
Chapter 129
Chapter 128
Chapter 127
Chapter 126
Chapter 125
Chapter 124
Chapter 123
Chapter 122
Chapter 121
Chapter 120
Chapter 119
Chapter 118
Chapter 117
Chapter 116
Chapter 115
Chapter 114
Mahiro and the Cosplay Photoshoot
Chapter 113
Mahiro and the Ecological Research Duo
Chapter 112
Mahiro and Gender Topsy-Turvy
Chapter 111
Mahiro and the Fun-filled Lion's Den
Chapter 110
Mahiro and the Demon of the Prefect Council
Chapter 109
Mahiro and a Healthy Beauty Regimen
Chapter 108.5
A DATE WITH NEMU
Chapter 108
Mahiro and Bodyguards
Chapter 107.9
Minato-kun is Done For? 3
Chapter 107.5
MAHIRO AND THE MAKEOVER
Chapter 107
Mahiro and Popularity Rankings
Chapter 106
Mahiro and Sharing Secrets
Chapter 105
Mahiro and an Offline Adventure
Chapter 104.5
MAHIRO AND THE MOTHERLY EMBRACE
Chapter 104
Mahiro and Mother's Day
Chapter 103
Mahiro and Heaven or Hell
Chapter 102.2
Aoi-chan Edition
Chapter 102.1
Niichi-chan Edition
Chapter 102
Mahiro and a Technological Nightmare
Chapter 101.5
MAHIRO AND THE FEMALE CHARACTERS
Chapter 101
Mahiro and a Celebration
Chapter 100.9
Onii-chan's Drawing Book
Chapter 100.5
MAHIRO AND THE CAT ARMY......
Chapter 100
Mahiro and a Good Day for an Experiment
Chapter 100
Chapter 99.5
Mahiro and Getting a License + Doujin Issue 33 Extras
Chapter 99
Mahiro and the Autobahn
Chapter 99
Chapter 98.5
Mahiro and Being a Small Fry Human
Chapter 98
Mahiro and a One-Night Stay
Chapter 98
Chapter 97
Mahiro and Crossing the Line
Chapter 97
Chapter 96
Mahiro and a Token of Appreciation
Chapter 96
Chapter 95.9
Minato-kun is Done For? 2
Chapter 95.5
Miyo and the Date
Chapter 95
Mahiro and the University Expedition Squad
Chapter 95
Chapter 94
Mahiro and the New School Year, Once Again
Chapter 94
Chapter 93.5
The Boys and Another Shot
Chapter 93
Mahiro and a Special Treat
Chapter 93
Chapter 92.5
Asahi and Growth
Chapter 92
Mahiro and a Maiden's Secret
Chapter 92
Chapter 91.5
Nemu and Nodoka
Chapter 91
Mahiro and Marriage
Chapter 91
Chapter 90.9
Volume 9 Special Edition Extras
Chapter 90.8
Mahiro and Mama (Revisited)
Chapter 90.5
Chapter 90
Mahiro and Celebrating Success
Chapter 90
Chapter 89
Mahiro and a Home Visit
Chapter 89
Chapter 88.5
Chapter 88
Mahiro and Romantic Antics
Chapter 88
Chapter 87
Mahiro and Special Techniques
Chapter 87
Chapter 86.9
Minato-kun is Done For? 1.5
Chapter 86.5
Special: Asahi's Birthday
Chapter 86
Mahiro and Overflowing Maternal Instincts
Chapter 86
Chapter 85.5
Chapter 85
Mahiro and a Stressful Reunion (Part 2)
Chapter 85
Chapter 84
Mahiro and a Stressful Reunion (Part 1)
Chapter 84
Chapter 83.9
Minato-kun is Done For? (Full Version)
Chapter 83
Mahiro and the New Year's Tour
Chapter 83
Chapter 82.5
Chapter 82
Mahiro and a Silent Night
Chapter 82
Chapter 81.9
Minato-kun is Done For? (Preview Version)
Chapter 81.8
Non-Mahiro Special: Aoi-chan Edition
Chapter 81.5
Chapter 81
Mahiro and Conflicting Views
Chapter 81
Chapter 80.8
Mahiro and the Growing Gal Gang + Volume 8 Extras
Chapter 80
Mahiro and the Secret Engagement
Chapter 80
Chapter 79
Mahiro and the Gal Gang
Chapter 79
Chapter 78.9
Mihari's Research Lab
Chapter 78.5
The Boys and MMORPGs
Chapter 78
Mahiro and MMORPGs Revisited
Chapter 78
Chapter 77
Mahiro and the Farewell Party
Chapter 77
Chapter 76.9
The Research Lab's Mihari-chan
Chapter 76.1
Blu-Ray Box Volume 2 Add-in Comic
Chapter 76
Mahiro and a Close Call
Chapter 76
Chapter 75
Mahiro and the Siren's Call
Chapter 75
Chapter 74.99
Mihari's Birthday Venue
Chapter 74.5
Everyone and the Blackout
Chapter 74.1
Blu-Ray Box Volume 1 Add-in Comic
Chapter 74
Mahiro and a Night Together
Chapter 74
Chapter 73.5
Non-Mahiro Special: Nii-chan Edition
Chapter 73.1
Mahiro-chan's Birthday Venue (2023)
Chapter 73
Mahiro and Big Bro's Secrets
Chapter 73
Chapter 72.9
The Boys Are Done For Too! + Omnibus 22-23-24 Extras
Chapter 72
Mahiro and an Admiration
Chapter 72
Chapter 71.5
Mahiro and the Magazine Model
Chapter 71
Mahiro and the selfie boom
Chapter 71
Chapter 70.9
Volume 7 Special Booklet
Chapter 70.8
Volume 7 Extras
Chapter 70.7
Mahiro and a Discussion on Cosplay
Chapter 70
Mahiro and an autumn outing
Chapter 70
Chapter 69.99
Nayutan's Birthday Venue
Chapter 69.5
Mahiro and a Moment of Glory
Chapter 69
Mahiro and the Youthful Sports Festival
Chapter 69
Chapter 68.99
Momiji Birthday Venue
Chapter 68
Mahiro and the World of Hobbies
Chapter 68
Chapter 67.99
Kaede-chan's birthday venue
Chapter 67
Mahiro and Male Pride
Chapter 67
Chapter 66.5
The Boys and Changing Shifts
Chapter 66
Mahiro and the Tempting Culture Festival (Part 2)
Chapter 66
Chapter 65
Mahiro and the Tempting Culture Festival (Part 1)
Chapter 65
Chapter 64
Mahiro and a Healthy Diet
Chapter 64
Chapter 63.99
Omnibus 19-20-21 Extras
Chapter 63.5
Momiji and Panties
Chapter 63
Mahiro and Staying Over Because of Rain
Chapter 63
Chapter 62.5
Nemu and Summer Vacation
Chapter 62.1
Mihari-chan's Birthday Venue
Chapter 62
Mahiro and a 2nd Semester Debut
Chapter 62
Chapter 61
Mahiro and Summer Festival
Chapter 61
Chapter 60
Mahiro and Summer Homework
Chapter 60
Chapter 59
Mahiro and spring cleaning
Chapter 59
Chapter 58
Mahiro and the Marine Ranger (Part 2)
Chapter 58
Chapter 57
Mahiro and the Marine Ranger (Part 1)
Chapter 57
Chapter 56
Mahiro and The Battle Plan Meeting
Chapter 56
Chapter 55
Mahiro and a Summer Adventure
Chapter 55
Chapter 54.9
Omnibus 16-17-18 Extras
Chapter 54.7
Mahiro and Harems
Chapter 54.5
Mahiro and the serene mind
Chapter 54
Mahiro and School Ghost Stories
Chapter 54
Chapter 53.5
Boys and Girls
Chapter 53
Mahiro and the North Wind and Sun
Chapter 53
Chapter 52
Mahiro and the Little Garden
Chapter 52
Chapter 51
Mahiro and Passing the Rainy Season
Chapter 51
Chapter 50.5
Chapter 50
Mahiro and Swim Classes (Part 2)
Chapter 50
Chapter 49
Mahiro and Swim Classes (Part 1)
Chapter 49
Chapter 48.5
MAHIRO AND THE PARENT-TEACHER CONFERENCE
Chapter 48
Mahiro and Class Observation
Chapter 48
Chapter 47
Mahiro and the Sunny Girl
Chapter 47
Chapter 46.5
Mihari and Memories of Stickers
Chapter 46
Mahiro and Sticker Collecting (fixed)
Chapter 46
Chapter 45.9
Omnibus 13-14-15 Extras
Chapter 45.7
Mahiro and Visible Undergarments
Chapter 45
Mahiro and the Season for New Clothes
Chapter 45
Chapter 44
Mahiro and the Secret BBQ
Chapter 44
Chapter 43.5
Chapter 43
Mahiro and Fragrances
Chapter 43
Chapter 42.6
EX3 Special - Mahiro and a Hair's Breadth from Danger!
Chapter 42.5
[TEMP 1]41.3+41.7 & 42.5 & Mini Extra (2 of 10)
Chapter 42
Mahiro and the Gift of Memories
Chapter 42
Chapter 41
Mahiro and the Physical Examination
Chapter 41
Chapter 40.99
Bonus Illustration
Chapter 40.8
Mihari and Skipping Grades
Chapter 40.6
Mini Extras [Complete]
Chapter 40.5
Mahiro and Barefoot
Chapter 40
Mahiro and an Important Secret (Part 2)
Chapter 40
Chapter 39
Mahiro and an Important Secret
Chapter 39
Chapter 38.5
Momiji and Massages
Chapter 38
Mahiro and an Appreciated Break
Chapter 38
Chapter 37.5
Mihari and High School Girls
Chapter 37
Mahiro and a Girl's Mannerisms
Chapter 37
Chapter 36.9
Mahiro's Weekday Routine + Omnibus 10-11-12 Extras
Chapter 36.5
Mahiro and a Present
Chapter 36
Mahiro and a Surprise
Chapter 36
Chapter 35.6
EX2 Special - I am Mahiro and I am Mihari
Chapter 35
Mahiro and the Guidance of Fortunes
Chapter 35
Chapter 34.5
Chapter 34.5 (1+2+3)
Chapter 34
Mahiro and the Adult's Door
Chapter 34
Chapter 33.5
Mahiro and Handmade
Chapter 33
Mahiro and Valentine's
Chapter 33
Chapter 32.5
Mahiro and Drinks
Chapter 32
Mahiro and a Surprise Visit
Chapter 32
Chapter 31
Mahiro and Charming Bare Legs
Chapter 31
Chapter 30.9
Chapter 21-30 Mini Extras [Complete]
Chapter 30.8
Asahi and Momiji
Chapter 30.5
Mahiro and Hot Kiss
Chapter 30
Mahiro and the Coming and Going Year
Chapter 30
Chapter 29
Mahiro and a Double Date
Chapter 29
Chapter 28.1
Mahiro and Girl's Night (Second Part) [Tank Version]
Chapter 28
Mahiro and Girl's Night (Second Part) [Pixiv Version]
Chapter 28
Chapter 27.99
Omnibus 7-8-9 Extras
Chapter 27.5
Including Extra (25.5 - 26.5 - 27.5)
Chapter 27
Mahiro and Girl's Night (First Part)
Chapter 27
Chapter 26
Mahiro and Patissier
Chapter 26
Chapter 25
Mahiro and Finals
Chapter 25
Chapter 24.5
Part 1: Mahiro and Bento & Part 2: Mihari and Bento
Chapter 24
Mahiro and Common Interests
Chapter 24
Chapter 23
Mahiro and the Fun Weekend
Chapter 23
Chapter 22.5
EX Special - Mahiro and an Uneventful Holiday
Chapter 22
Mahiro and the Harsh Lesson
Chapter 22
Chapter 21.5
Extras
Chapter 21
Mahiro and the First Day of School (V2)
Chapter 21
Chapter 20.9
Chapter 11-20 Mini Extras
Chapter 20.5
Mihari and Dresses + Mihari (afterwards) and Dresses
Chapter 20
Mahiro and Middle Schoolers (v2)
Chapter 20
Chapter 19
Mahiro and Uploading Videos
Chapter 19
Chapter 18.99
Omnibus 4-5-6 Extras
Chapter 18.5
Part 1: Mahiro and a "Comrade's" Return & Part 2: Mahiro and Perms
Chapter 18
Mahiro and the Onsen Panic (Second Part)
Chapter 18
Chapter 17
Mahiro and the Onsen Panic (First Part)
Chapter 17
Chapter 16
Mahiro and the Hair Salon
Chapter 16
Chapter 15.5
Siblings and Kotatsu
Chapter 15
Mahiro and Party Night
Chapter 15
Chapter 14
Mahiro and a Little Adventure
Chapter 14
Chapter 13
Mahiro and a Wholesome Relationship
Chapter 13
Chapter 12.5
Mahiro and Nichiasa
Chapter 12
Mahiro and a Lonely Night
Chapter 12
Chapter 11
Mahiro and Adventure
Chapter 11
Chapter 10.99
Omnibus 1-2-3 Extras
Chapter 10.9
Chapter 1-10 Mini Extras
Chapter 10.5
Mahiro and Helping Out & OMAKE - Mihari and Onii-chan
Chapter 10
Mahiro and Special Home Security
Chapter 10
Chapter 9.5
Mahiro and the Two's Secret
Chapter 9
Mahiro and a Girl's Vacation
Chapter 9
Chapter 8.5
Mahiro and Gacha (v2)
Chapter 8
Mahiro and New Game
Chapter 8
Chapter 7
Mahiro and Encounters with the Unknown
Chapter 7
Chapter 6.5
Mahiro and Going in Circles
Chapter 6
Mahiro and the Secret Garden
Chapter 6
Chapter 5.5
Mahiro and Comfort for Many Days
Chapter 5
Mahiro and a Melancholic Day
Chapter 5
Chapter 4
Mahiro and MMORPG
Chapter 4
Chapter 3
Mahiro and Identity
Chapter 3
Chapter 2
Mahiro and the Dangerous Mirror
Chapter 2
Chapter 1.5
Mahiro and the Toilet
Chapter 1
Mahiro and the Unpleasurable Body
Chapter 1
About ONIMAI: I'm Now Your Sister!
Mahiro Oyama was just a normal erotic-game loving dude...until he woke up one morning as a woman! Turns out his mad-scientist little sister, Mihari, tried out one of her new experiments on him...with a disastrous… Read full synopsis →
Updated Apr 03, 2026•Ongoing
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